Dialing in my analog rig - Need help

Rodmann:That's about a degree if my math is right and it is a 9" tonearm.So the LP thickness is not setting the optimum SRA. Do you agree?

OOPS again to an earlier thread! I meant a 200 gram LP NOT a 200 mm one! I must proof these threads better!

It's a Magnepan Unitrac I, and measures 10" from the pivot point(set back from post) to stylus. Most measure distortion figures, with regards to VTA/SRA setting, but losses of sound stage width, hall ambience cues and such(while easily discernible, given a well recorded disc & good system) are not actually quantifiable.

I agree. That is why in the final analysis you have to trust your ears!

Azimuth adjustment;

Always start with the cartridge as physically neutral as possible as viewed from the front. It should be as flat as possible. Your “best setting” is here or not more than 3 degrees from this position, either clockwise or counterclockwise.

To verify the best position, use a test record where one channel is modulated at a time, and LISTEN (or measure properly) the OTHER channel for crosstalk or bleed through. Do the same thing vice-versa with the other channel. When the crosstalk, or bleed through is roughly the same, that is the best azimuth. Many cartridges can be azimuth adjusted in this manner, because the bleed through for each channel will be roughly the same for most cartridges when the azimuth is correct.

There is a caveat with this procedure. Not all cartridges have identical separation or bleed through amounts when comparing channels. For example, one channel may be 6dB “worse” than the other at the BEST azimuth setting for the channel with poorer crosstalk performance. In other words, one channel may have extremely good crosstalk when compared with the other. These differences do not indicate a defective cartridge, they simply point out how difficult it is to make a cartridge with identical separation performance. So, how does one adjust under this situation??

The trick is to find the critical azimuth point for the WORST channel where it JUST achieves best separation and to stop there. It is likely that you will find that continued adjustment in that direction will NOT result in improvement of separation.

In other words, if one channel is always much better in terms of less crosstalk than the other, tune the azimuth by using the worse of the two channels. Again, the best way to tune the “worst” channel is to find the point where the crosstalk “just” becomes minimized and go no farther. Verify that the other channel is still better in that it has less crosstalk. If you NOW FIND that you have NOT gone more than a tiny bit off the neutral position to do this, you have probably hit the best azimuth.
If you find you are way off neutral, that is wrong, and something else is wrong with your setup.

Anti-skating…..

Make sure that the anti-skating is well set; there are many ways to tell, but this is a method suggested by Frank Schroder

When you have it adjusted right, the arm will track on the SURFACE of the record (not in the groove) at the end of the record on the un-pressed flat space where the run-out groove is – it should track INWARDS toward the center at a slower rate than IF IT WERE in the end groove. If you do that, then the best average Anti-Skating is set correctly.

This can help - especially with medium or high compliance cartridges - LOOK at the position of the cantilever when it is up in the air, and when it is on the record, both at the beginning, and at the end. Look for a change in position both initially upon set-down, as well as after 1-2 minutes. DO THIS BEFORE adjusting as above - it should not change position - if it does, the A-S is VERY wrong.

ATTENTION VPI OWNERS:

If you have an under-slung counterweight (MOST VPI tables) you will greatly benefit from obtaining the Soundsmith “Counter-Intuitive”, a device that allows you to independently and easily perform fine adjustments of VTF and Azimuth. If your VPI counter weight is all the way forward already, you will need to offset the small amount of weight added by the Counter Intuitive with a set of EZ-Mount screws. The links are here:
http://www.sound-smith.com/intuitive/index.html
http://www.sound-smith.com/screwset/index.html

AZIMUTH VPI ISSUES:

Some of us who own VPI tables are aware that in the past, VPI’s suggestion was to twist the signal cable one way or the other to affect a proper antiskating force. I have found that this is a fairly gross method, which does not allow for fine adjustment. VPI has wisely come out with an anti-skating device, which is strongly advised. One must appreciate however, that its use does take some time to get right, as one is working against not only the skating force for the cartridge itself, but the side force from the stiffness of the signal cable as well. I have had some luck using the VPI anti-skating device by adding small brass washers (if needed), sometimes between 3 and 5 of them, to the far small arm that does not have the nylon string attached. I positioned them between the rubber o-rings that they supply to hold them in place and at the proper height – and it allowed me to adjust the force to exactly what was needed. Patience is often required.

The way to start with the VPI arms is to twist the wire till the stylus tracks INWARDS on the surface near the end lead out groove, THEN add enough Anti-skating to slow it down to the desired rate as described above.

Peter Ledermann/Soundsmith